Evolution of behaviour

Question 1

Definition of phylogenetic tree?

Answer 1

-map of the evolutionary relatedness of different species

Question 2

What is the adaptive landscape?

Answer 2

-recombination of genes within an animal’s genotype and the fitness that we get from it

Question 3

Definition of epistasis?

Answer 3

• expression of one depends upon the presence of others around it
• gene can be expressed or repressed by the other genes around

Question 4

Definition of divergent evolution?

Answer 4

-evolution of different features from a common ancestor resulting in differences between species

Question 5

Example of divergent evolution in animals?

Answer 5

• forearm in species
• monkey,whale,pig and bird all have different uses for the arm so have adapted them to fit those uses (all have 5 bones but in different forms)

Question 6

Definition of convergent evolution?

Answer 6

-evolution of similar features in unrelated species due to similar environmental pressures

Question 7

What factors complicate evolution?

Answer 7

• missing species
• changed environment
• changed selection pressures

Question 8

How does missing species complicate evolution?

Answer 8

• can’t conclude where behaviours are from if there’s gaps in our records
• e.g. can’t understand how we can talk while apes before us can’t

Question 9

How does a changed environment complicate evolution?

Answer 9

-behaviour can develop in response to localised climate change which will increase the fitness of the individual in the long-term

Question 10

Example of changed environment complicating evolution?

Answer 10

• tiger
• didn’t used to be restricted to Asia, used to stretch into the colder climates
• when the Ice Age retreated they were marooned in tropical rainforests as the climate changed
• tigers have adapted to bathing to cope with the warmer conditions

Question 11

How does changed selection pressures complicate evolution?

Answer 11

-behaviours can change the selective pressures on future generations

Question 12

Example of changed selection pressure complicating evolution?

Answer 12

• beavers
• building dams completely alters the flora and fauna of the environment (fish,birds etc) so alter who’s able to survive in the environment

Question 13

Definition of parsimony?

Answer 13

-process that requires the least number of changes

Question 14

Why does behaviours arise?

Answer 14

• pre-existing behaviours (ritualisation or co-option)
• pre-existing biases (sensory exploitation)
• adaptive co-evolution (coordinated change between 2 or more elements of ecology/morphology/behaviour)